从angular 7中的孙子组件调用方法

import { Component, ViewChild } from '@angular/core';
import { GrandchildComponent } from './grandchild.component';

@Component({
  selector: 'app-parent',
  template: `
    <app-child></app-child>
  `
})
export class ParentComponent {
  @ViewChild(GrandchildComponent) grandchild: GrandchildComponent;

  callGrandchildMethod() {
    this.grandchild.someMethod();
  }
}

import { Component } from '@angular/core';

@Component({
  selector: 'app-grandchild',
  template: `
    <p>Grandchild Component</p>
  `
})
export class GrandchildComponent {
  someMethod() {
    console.log('Method called from grandchild component');
  }
}

<button (click)="callGrandchildMethod()">Call Grandchild Method</button>